1. Field of the Invention
This invention relates to gripper elements for sports shoes, and more particularly, to shoes for use on synthetic surfaces such as Astroturf.
Athletic shoes, as used for football, baseball, soccer, track, golf, and other sports require a cleat, spike, or other gripping element, affixed to the sole, so that the wearer of the shoe will not slip on the surface he is walking or running upon. Artificial turf and other synthetic surfaces, in particular, are prone in inducing slippage with conventional cleated athletic shoes.
The subject invention is of a cleat or gripper element which can be affixed either permanently or by a removable fastener to the outsole of a sports shoe, and which provides a highly slip-resistant shoe adapted to use on artificial turf.
2. The prior art employs cleats of fixed construction, made of plastic or metal, which, because of slippage, is not suitable for use on artificial turf. Moreover, conventional spikes tend to lodge in the surface of plastic tracks, requiring excessive force to be exerted in their removable. Hence the use of sports shoes with conventional spikes or gripper elements on plastic tracks and artificial turf for the staging of athletic competition has been unsatisfactory.
The use of conventional spikes has been discontinued for track shoes used on plastic tracks. A gripper element particularly designed for plastic tracks is described in U.S. Pat. No. 3,859,739 issued Jan. 14, 1975 to A. Dassler, where the body of the element prevents undue penetration into a plastic track. However, such spikes still possess the limitations described above the respect to artificial turf.
It has been found that a resiliently mounted spike is capable of affording excellent traction on artificial turf, while being capable of design variation to suit the weight and activities of the wearer. The advantage of this invention over the prior art is that it provides a highly stable, adjustable exposure gripper element, suitable for use where conventional cleats are ineffective. Wearing parts are replaceable, and the spring action provides a range of adjustment to suit the weight and activities of the wearer, as well as enhancing the life of the invention by allowing reduced wear on the contact surfaces.
A sports shoe with spring-loaded gripper elements is described in U.S. Pat. No. 3,496,656 issued Feb. 24, 1970 to W. R. Caine. However this invention was intended only to impart a springiness to the wearer's feet, and suffers a loss of penetration power when compressed under the weight of the wearer, as compared with the subject invention, which provides increased gripping power under these conditions.